Printer head using shape memory alloy and method for manufacturing the same

ABSTRACT

Disclosed are a printer head using shape memory alloy and a method for manufacturing the same. The printer head using shape memory alloy comprises a substrate; space parts defined at both sides of the substrate; a vibrating plate formed on the substrate such that it covers the space parts, to be vibrated while being changed in its contour depending upon temperature variation, the vibrating plate including a shape memory alloy layer and a silicon dioxide layer; an electrode formed on the vibrating plate to have a desired pattern; an insulating layer formed to protect the electrode; an ink storing chamber formed between the space parts of the substrate for storing ink; a pressure chamber defined on the vibrating plate for containing ink, the pressure chamber discharging ink by vibration of the vibrating plate; a fluid passage plate formed at a side of the pressure chamber; a fluid passage formed by the fluid passage plate for allowing the ink stored in the ink storing chamber to flow into the pressure chamber; a nozzle plate attached onto the fluid passage plate for allowing ink to be fired in the form of droplets when the vibrating plate is vibrated; and a plurality of nozzles formed in the nozzle plate and firing ink to a recording device.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a printer head using shape memory alloyand a method for manufacturing the same, and more particularly, thepresent invention relates to a method for manufacturing a printer headusing shape memory alloy by a semiconductor process and an etchingtechnique and a printer head using shape memory alloy manufactured bythe method.

2. Description of the Related Art

Generally, drop-on-demand (DOD) type printer heads which fire liquid inkonly under necessity are most widely used for ink jet printers. Use ofsuch DOD type printer heads has gradually increased in that they requireno electric charge or deflection of ink droplets and in that since highpressure is not needed, an easy printing is achieved by immediatelyfiring ink droplets under atmospheric pressure.

Typical firing principles of such printer heads include a heating typefiring method using a resistor, a vibration type firing method using apiezoelectric element, and a firing method using shape memory alloy,etc.

A printer head which adopts the heating type firing method generallyincludes a nozzle plate having a plurality of nozzles, a fluid passageplate coupled onto the nozzle plate and defining an ink storing chamberinto which ink is stored, a substrate coupled onto the fluid passageplate and covering the ink storing chamber, and a heating resistorembedded into the substrate.

In an ink firing device of a printer head which adopts a heating typefiring method, as shown in FIG. 1, ink is fired as described below.

First, if predetermined voltage is applied to a heating resistor 14,heat is generated. By the heat generated in the heating resistor 14, aircontained in ink adjacent the heating resistor 14 is expanded to createair bubbles. By these air bubbles, ink 16 inside an ink storing chamber10 is forced out through a nozzle 12 to be fired toward a recordingmedium.

The heating type firing method suffers from defects in that since ink isheated by heat generated in the heating resistor 14, the ink is likelyto be chemically degraded, and this degraded ink may be deposited ontoan inner surface of the nozzle 12 to clog the nozzle 12. Also, since theheating resistor 14 repeatedly generates heat upon application ofvoltage, a lifetime of the heating resistor 14 is shortened, and sinceonly water soluble ink should be used, preserving property for a printeddocument is deteriorated.

A printer head which adopts the vibration type firing method generallyincludes a nozzle plate having a plurality of nozzles, a fluid passageplate coupled onto the nozzle plate and defining an ink storing chamberinto which ink is stored, a substrate coupled onto the fluid passageplate and covering the ink storing chamber, and a piezoelectric elementcoupled onto the substrate and deforming the substrate while beingvibrated when electric power is applied thereto.

In an ink firing device of a printer head which adopts a vibration typefiring method, as shown in FIG. 2, ink is fired as described below.

If predetermined electric power is applied to a piezoelectric element24, the piezoelectric element 24 is vibrated. By vibration of thepiezoelectric element 24, volume of an ink storing chamber 20 ismomentarily changed, and ink 26 inside the ink storing chamber 20 isforced out through a nozzle 22 to be fired toward a recording medium.

The vibration type firing method using the vibration of thepiezoelectric element 24 provides an advantage in that since heat is notused, it is possible to use an ink other than water soluble ink andthereby a greater variety of choices are offered for ink. However, thevibration type firing method is encountered with problems in that sinceworkability for the piezoelectric element is impaired and especially, itis difficult to form the piezoelectric element, productivity is reduced.

FIG. 3 is a cross-sectional view schematically illustrating an inkfiring device of a printer head which uses shape memory alloy.

Shape memory alloy 32 which is in a flexurally deformed state isdisposed above an ink storing chamber 30. If the shape memory alloy 32which is in the flexurally deformed state is heated, the shape memoryalloy 32 is returned to its original flattened state after a flexurallydeformed portion is smoothed out.

As the shape memory alloy 32 is returned to its original flattenedstate, volume of the ink storing chamber 30 is decreased, and accordingto this, ink stored in the ink storing chamber 30 is fired through anozzle 36 to a recording device (not shown).

A printer head using shape memory alloy is classified into a first typewherein several shape memory alloy layers having different phasetransformation temperatures and different thicknesses are coupled onewith another to be flexurally deformed and a second type wherein a shapelimiting body and a shape memory alloy layer are coupled with each otherto be flexurally deformed.

Because printer heads of these types employ shape memory alloy of aplate-shaped configuration which has a thickness of 50-1,000 μm and anarea of 0.1-10 mm², power consumption is increased upon heating, heatingand cooling times are lengthened to decrease operation frequency, andprinting speed is lowered thereby deteriorating practicality of theentire printer head.

Moreover, since the shape memory alloy layer is thick and wide, itcannot be instantaneously heated, and displacement is slowly generatedover a relatively long period of time. Accordingly, due to the fact thata generated pressure is reduced, ink may not be fired or may not beproperly fired. Also, even in the case that ink is fired, because firingspeed of droplets is decreased, wetting may be caused and thereby it isdifficult to achieve stable firing of the droplets.

In addition, due to the fact that the shape memory alloy layer has aconfiguration of a plate which is large and thick and therefore, theentire structure thereof cannot but be enlarged, it is difficult tominiaturize the size of the printer head, integration density of nozzlesis diminished and printing resolution is deteriorated.

In other words, in the case that the shape memory alloy is used astaught in the conventional art, the pressure chamber of the printer headmust be enlarged such that it has a length of 100-10,000 μm and a widthof 50-500 μm. Accordingly, if a pressure chamber of this size is used,the entire structure of the printer head cannot but also be enlarged.

Besides, since the printer head is constructed in that several shapememory alloy layers which are bonded one with another and bent, or athin plate-shaped shape memory alloy layer and a shape limiting bodywhich are bonded with each other and bent, are attached by bonding to amain body in which an ink storing chamber is defined, it is difficult tomanufacture the printer head, and reliability is declined when the shapememory alloy is applied to the ink jet printer head which is required tobe vibrated several ten million times.

Also, while an efficient structure is needed to improve ink firingcapability, the conventional printer head using shape memory alloymainly discloses aspects related with a firing method and firingparticulars and does not mention structural details of the printer head.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made in an effort to solvethe problems occurring in the related art, and an object of the presentinvention is to provide a method for manufacturing a printer head usingshape memory alloy which is formed by a semiconductor thin filmmanufacturing process and has a thin film-shaped configuration and aprinter head using shape memory alloy which is manufactured by themethod, wherein configurations and sizes of a pressure chamber, a fluidpassage and an ink storing chamber as being main components of theprinter head are optimized to improve ink firing capability.

In order to achieve the above object, according to one aspect of thepresent invention, there is provided a method for manufacturing aprinter head using shape memory alloy, comprising the steps of:preparing a silicon substrate having a flat configuration; thermallyoxidizing the silicon substrate to form a pair of silicon dioxide layerson both surfaces of the silicon substrate, respectively; forming a shapememory alloy layer on one of the pair of silicon dioxide layers by asemiconductor thin film forming process; thermally treating the formedshape memory alloy layer; patterning the shape memory alloy layer;patterning the silicon dioxide layers formed on both surfaces of thesilicon substrate, respectively; forming an electrode on the shapememory alloy layer to have a desired pattern; forming an insulatinglayer for protecting the electrode; forming a body of the printer headby etching the silicon substrate on which the electrode and insulatinglayer are formed; separately forming a nozzle plate into which aplurality of nozzles are formed; forming a fluid passage plate bybonding a photosensitive dry film onto the nozzle plate and patterningthe photosensitive dry film; and bonding the nozzle plate and the fluidpassage plate onto the body of the printer head. The method can furthercomprise the steps of: forming an auxiliary plate; applying aphotosensitive dry film on the auxiliary plate and patterning thephotosensitive dry film; and bonding the auxiliary plate on which thephotosensitive dry film is patterned, onto the other of the pair ofsilicon dioxide layers.

According to another aspect of the present invention, there is provideda method for manufacturing a printer head using shape memory alloy,comprising the steps of: preparing a silicon substrate having a flatconfiguration; thermally oxidizing the silicon substrate to form a pairof silicon dioxide layers on both surfaces of the silicon substrate,respectively; forming a shape memory alloy layer on one of the pair ofsilicon dioxide layers by a semiconductor thin film forming process;thermally treating the formed shape memory alloy layer; patterning theshape memory alloy layer; patterning the silicon dioxide layers formedon both surfaces of the silicon substrate, respectively; forming anelectrode on the shape memory alloy layer to have a desired pattern;forming an insulating layer for protecting the electrode; applying aphotosensitive dry film onto the insulating layer and patterning thephotosensitive film; forming a body of the printer head by dry etchingthe formed silicon substrate; separately forming a nozzle plate intowhich a plurality of nozzles are formed; and bonding the nozzle plateonto the body of the printer head. The method can further comprise thesteps of: forming an auxiliary plate; applying a photosensitive dry filmon the auxiliary plate and patterning the photosensitive dry film; andbonding the auxiliary plate on which the photosensitive dry film ispatterned, onto the other of the pair of silicon dioxide layers.

According to still another aspect of the present invention, there isprovided a method for manufacturing a printer head using shape memoryalloy, comprising the steps of: preparing a silicon substrate having aflat configuration; thermally oxidizing the silicon substrate to form apair of silicon dioxide layers on both surfaces of the siliconsubstrate, respectively; forming a shape memory alloy layer on one ofthe pair of silicon dioxide layers by a semiconductor thin film formingprocess; thermally treating the formed shape memory alloy layer;patterning the shape memory alloy layer; patterning the silicon dioxidelayers formed on both surfaces of the silicon substrate, respectively;forming an electrode on the shape memory alloy layer to have a desiredpattern; forming an insulating layer for protecting the electrode;applying a photosensitive dry film onto the insulating layer andpatterning the photosensitive film to define a body of the printer head;separately forming a nozzle plate into which a plurality of nozzles areformed; bonding the nozzle plate onto the body of the printer head; anddry etching the silicon substrate. The method can further comprise thesteps of: forming an auxiliary plate; applying a photosensitive dry filmon the auxiliary plate and patterning the photosensitive dry film; andbonding the auxiliary plate on which the photosensitive dry film ispatterned, onto the other of the pair of silicon dioxide layers.

According to yet still another aspect of the present invention, there isprovided a printer head using shape memory alloy comprising: asubstrate; space parts defined at both sides of the substrate; avibrating plate formed on the substrate such that it covers the spaceparts, to be vibrated while being changed in its contour depending upontemperature variation, the vibrating plate including a shape memoryalloy layer and a silicon dioxide layer; an electrode formed on thevibrating plate to have a desired pattern; an insulating layer formed toprotect the electrode; an ink storing chamber formed between the spaceparts of the substrate for storing ink; a pressure chamber defined onthe vibrating plate for containing ink, the pressure chamber dischargingink by vibration of the vibrating plate; a fluid passage plate formed ata side of the pressure chamber; a fluid passage formed by the fluidpassage plate for allowing the ink stored in the ink storing chamber toflow into the pressure chamber; a nozzle plate attached onto the fluidpassage plate for allowing ink to be fired in the form of droplets whenthe vibrating plate is vibrated; and a plurality of nozzles formed inthe nozzle plate for firing ink to a recording device.

BRIEF DESCRIPTION OF THE DRAWINGS

The above objects, and other features and advantages of the presentinvention will become more apparent after a reading of the followingdetailed description when taken in conjunction with the drawings, inwhich:

FIG. 1 is a cross-sectional view schematically illustrating an inkfiring device of a printer head which adopts a heating type firingmethod;

FIG. 2 is a cross-sectional view schematically illustrating an inkfiring device of a printer head which adopts a vibration type firingmethod using a piezoelectric element;

FIG. 3 is a cross-sectional view schematically illustrating an inkfiring device of a printer head which uses shape memory alloy;

FIGS. 4 through 12 are cross-sectional views for explaining a method formanufacturing a printer head using shape memory alloy in accordance withan embodiment of the present invention;

FIGS. 13 through 22 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy in accordancewith another embodiment of the present invention;

FIGS. 23 through 32 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy in accordancewith another embodiment of the present invention;

FIGS. 33 through 43 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy in accordancewith another embodiment of the present invention;

FIG. 44 is a cross-sectional view illustrating a printer head usingshape memory alloy, manufactured according to the present invention;

FIG. 45 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention;

FIG. 46 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention;

FIG. 47 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention;

FIG. 48 is a plan view schematically illustrating the printer headaccording to the present invention;

FIG. 49 is a cross-sectional view schematically illustrating a firingdevice of the printer head according to the present invention; and

FIG. 50 is a plan view illustrating an actuator of the printer headaccording to the present invention.

DETAILED DESCRIPTION

Hereinafter, the present invention will be described in detail.

A method for manufacturing a printer head using shape memory alloy ofthe present invention will be first described. The method formanufacturing a printer head using shape memory alloy is classified intothree methods.

A first method for manufacturing a printer head using shape memory alloyof the present invention will be described below.

A flat plate-shaped silicon substrate is used as a substrate. Thesilicon substrate is thermally oxidized to form a pair of thermallyoxidized films on both surfaces thereof, respectively. In order tothermally oxidize both surfaces of the silicon substrate, it is commonto use a procedure wherein mixed gas of oxygen and water vapor issupplied at 1,100° C.

A silicon dioxide layer which is formed on the surface of the substrateserves as a second thin film in addition to shape memory alloy in theform of a thin film, when manufacturing of the printer head iscompleted. Further, since the silicon dioxide layer has compressivestress, it provides the shape memory alloy with restoring force forenabling the shape memory alloy flattened by heating to be flexurallydeformed again while being cooled.

If the silicon dioxide layer is thick, energy consumption is increasedwhen the shape memory alloy is flattened by heating, and if the silicondioxide layer is thin, restoring force for restoring the shape memoryalloy to its flexed state is reduced. Accordingly, it is preferred thatthe silicon dioxide layer has a thickness of 0.3-2.0 μm.

Shape memory alloy is deposited onto the thermally oxidized film of thesilicon dioxide, which is formed on the silicon substrate, by asemiconductor thin film manufacturing process such as sputtering or thelike, to form a thin film of shape memory alloy. The thin film of shapememory alloy is then thermally treated, that is, baked. If the shapememory alloy layer is thick, because various problems as mentioned inthe descriptions for the related art are induced, it is preferred thatthe shape memory alloy layer has a thickness of 0.5-5 μm.

The shape memory alloy layer which is formed on the substrate and isthermally treated, is patterned to a desired pattern. As a method forpatterning the shape memory alloy layer, a method for patterning byvirtue of photolithography which uses a photoresist, or the like isused.

In implementing the photolithography, a photoresist is applied on theshape memory alloy layer by a method such as spin coating, laminating orthe like to a predetermined thickness, and then, is exposed to light todefine a desired pattern. After etching the photoresist which is formedto define the desired pattern, the shape memory alloy layer is alsopatterned to a desired pattern.

After the shape memory alloy layer is patterned to have the desiredpattern, the silicon dioxide layers which are formed on both surfaces ofthe substrate, are further patterned. As a method for patterning thesilicon dioxide layers, a method which is the same as that used forpatterning the shape memory alloy layer is employed.

An electrode is formed on a vibrating plate which is formed by thepatterned shape memory alloy layer and the patterned silicon dioxidelayer, to a desired pattern. At this time, it is common that theelectrode is made of material selected from a group consisting ofaluminum (Al), gold (Au), platinum (Pt) and silver (Ag). The electrodeis formed such that the vibrating plate is exposed to the outside abovespace parts.

After patterning the electrode, an insulating layer for protecting theelectrode is formed on the electrode. As material of the insulatinglayer, material which does not conduct current well, such as a siliconoxide, a silicon nitride, etc. is used. As a method for forming theinsulating layer, a method which is the same as that used for patterningthe shape memory alloy layer can be employed.

After the silicon substrate is patterned, the silicon substrate iswholly etched to form space parts and an ink storing chamber, thereby toform a body of a printer head.

At this time, as an etching method, both a wet etching technique and adry etching technique can be used.

However, in the case that the substrate is etched using a wet etchingtechnique, an etching face is not vertical and forms an angle withrespect to a vertical line, due to a difference in etching ratedepending upon crystal orientation. If etching is performed from abottom surface of the substrate, a distance between an ink storingchamber and a pressure chamber is lengthened due to an etching angle bya length which is no less than a thickness of a wafer, thereby todeteriorate the ink firing characteristic. Consequently, in order toshorten the distance between the ink storing chamber and the pressurechamber, etching must be performed from an upper part of the wafer.

In the meanwhile, if the substrate is etched using a dry etchingtechnique, since an etching face is vertical, it is possible to reducethe distance between the ink storing chamber and the pressure chamber.Further, since integration density of nozzles can be raised, a structureof the printer head can be made small, an entire printer head can beminiaturized, and printing resolution can be elevated. Therefore, it ispreferred to use a dry etching technique.

If the space parts are formed by etching the substrate on which theshape memory alloy layer is formed, the shape memory alloy layer isflexurally deformed due to a buckling phenomenon by the compressionstress which resides in the silicon dioxide layer, and is maintained asit is flexurally deformed.

A nozzle plate in which a plurality of nozzles are defined is separatelyformed. A photosensitive dry film is bonded to the nozzle plate. Byexposing the bonded photosensitive dry film and patterning thephotosensitive dry film to a desired pattern, a fluid passage plate isprepared.

The fluid passage plate of the nozzle plate, which is patterned to thedesired pattern and the body of the printer head manufactured asdescribed above are bonded with each other to complete the printer head.The fluid passage plate and the printer head are bonded with each otherwhile a predetermined pressure is applied at a high temperature.

A second method for manufacturing a printer head using shape memoryalloy of the present invention will be described below.

Of course, at this time, a flat plate-shaped silicon substrate is usedas a substrate. The silicon substrate is thermally oxidized to form apair of thermally oxidized films on both surfaces thereof, respectively.In order to thermally oxidize both surfaces of the silicon substrate, itis common to use a procedure wherein mixed gas of oxygen and water vaporis supplied at 1,100° C.

It is preferred that a silicon dioxide layer formed on the surface ofthe substrate has a thickness of 0.3-2.0 μm.

Shape memory alloy is deposited onto the thermally oxidized film of thesilicon dioxide, which is formed on the silicon substrate, by asemiconductor thin film manufacturing process such as sputtering or thelike, to form a thin film of shape memory alloy. The thin film of shapememory alloy is then thermally treated, that is, baked. At this time, itis preferred that the shape memory alloy layer has a thickness of 0.5-5μm.

The formed shape memory alloy layer is patterned to a desired pattern.As a method for patterning the shape memory alloy layer, a method forpatterning by virtue of photolithography which uses a photoresist, orthe like is used.

In implementing the photolithography, a photoresist is applied on theshape memory alloy layer by a method such as spin coating, laminating orthe like to a predetermined thickness, and then, is exposed to light todefine a desired pattern. After etching the photoresist which is formedto define the desired pattern, the shape memory alloy layer is alsopatterned to a desired pattern.

After the shape memory alloy layer is patterned to have the desiredpattern, the silicon dioxide layers which are formed on both surfaces ofthe substrate, are further patterned. As a method for patterning thesilicon dioxide layers, a method which is the same as that used forpatterning the shape memory alloy layer is employed.

An electrode is formed on a vibrating plate which is formed by thepatterned shape memory alloy layer and the patterned silicon dioxidelayer, to a desired pattern. At this time, it is common that theelectrode is made of material selected from a group consisting ofaluminum (Al), gold (Au), platinum (Pt) and silver (Ag). The electrodeis formed such that the vibrating plate is exposed to the outside abovespace parts.

After patterning the electrode, an insulating layer for protecting theelectrode is formed on the electrode. As material of the insulatinglayer, material which does not conduct current well, such as a siliconoxide, a silicon nitride, etc. is used. As a method for forming theinsulating layer, a method which is the same as that used for patterningthe shape memory alloy layer can be employed.

A photosensitive dry film is bonded onto the insulating layer which isformed. By exposing the bonded photosensitive dry film and patterningthe photosensitive dry film to a desired pattern, a fluid passage plateis prepared.

After patterning the photosensitive dry film, the silicon substrate iswholly etched by a dry etching technique to form space parts and an inkstoring chamber, thereby to form a body of a printer head. At this time,while it is possible to use a wet etching technique, as described above,it is more efficient that a dry etching technique is used.

If the space parts are formed by etching the substrate on which theshape memory alloy layer is formed, the shape memory alloy layer isflexurally deformed due to a buckling phenomenon by the compressionstress which resides in the silicon dioxide layer, and is maintained asit is flexurally deformed.

A nozzle plate in which a plurality of nozzles are defined is separatelyformed. The nozzle plate which is formed in this way, and the fluidpassage plate of the body of the printer head are bonded with each otherto complete the entire printer head. At this time, the nozzle plate andthe printer head are bonded with each other while a predeterminedpressure is applied at a high temperature.

A third method for manufacturing a printer head using shape memory alloyof the present invention will be described below.

Of course, at this time, a flat plate-shaped silicon substrate is usedas a substrate. The silicon substrate is thermally oxidized to form apair of thermally oxidized films on both surfaces thereof, respectively.In order to thermally oxidize both surfaces of the silicon substrate, itis common to use a procedure wherein mixed gas of oxygen and water vaporis supplied at 1,100° C.

It is preferred that a silicon dioxide layer formed on the surface ofthe substrate has a thickness of 0.3-2.0 μm.

Shape memory alloy is deposited onto the thermally oxidized film of thesilicon dioxide, which is formed on the silicon substrate, by asemiconductor thin film manufacturing process such as sputtering or thelike, to form a thin film of shape memory alloy. The thin film of shapememory alloy is then thermally treated, that is, baked. At this time, itis preferred that the shape memory alloy layer has a thickness of 0.5-5μm.

The shape memory alloy layer which is formed on the substrate ispatterned to a desired pattern. As a method for patterning the shapememory alloy layer, a method for patterning by virtue ofphotolithography which uses a photoresist, or the like is used.

In implementing the photolithography, a photoresist is applied on theshape memory alloy layer by a method such as spin coating, laminating orthe like to a predetermined thickness, and then, is exposed to light todefine a desired pattern. After etching the photoresist which is formedto define the desired pattern, the shape memory alloy layer is alsopatterned to a desired pattern.

After the shape memory alloy layer is patterned to have the desiredpattern, the silicon dioxide layers which are formed on both surfaces ofthe substrate, are further patterned. As a method for patterning thesilicon dioxide layers, a method which is the same as that used forpatterning the shape memory alloy layer is employed.

An electrode is formed on a vibrating plate which is formed by thepatterned shape memory alloy layer and the patterned silicon dioxidelayer, to a desired pattern. At this time, it is common that theelectrode is made of material selected from a group consisting ofaluminum (Al), gold (Au), platinum (Pt) and silver (Ag). The electrodeis formed such that portions of the vibrating plate are not covered bythe insulating layer, that is, they are exposed at portions above thespace parts.

After patterning the electrode, an insulating layer for protecting theelectrode is formed on the electrode. As material of the insulatinglayer, material which does not conduct current well, such as a siliconoxide, a silicon nitride, etc. is used. As a method for forming theinsulating layer, a method which is the same as that used for patterningthe shape memory alloy layer can be employed.

A photosensitive dry film is bonded onto the insulating layer which isformed. By exposing the bonded photosensitive dry film and patterningthe photosensitive dry film to a desired pattern, a fluid passage plateis prepared.

A nozzle plate in which a plurality of nozzles are defined is separatelyformed. The nozzle plate which is formed in this way, is bonded onto thefluid passage plate. At this time, the nozzle plate and the fluidpassage plate are bonded with each other while a predetermined pressureis applied at a high temperature.

The silicon substrate on which the nozzle plate is bonded is whollyetched by a dry etching technique to form space parts and an ink storingchamber, thereby to form a body of a printer head.

In the printer head manufactured by the methods described above, the inkstoring chamber is formed in a state that it is opened, and whenconnecting an ink cartridge, the ink cartridge and the body of theprinter head are directly connected with each other.

The ink storing chamber serves as a part which stores ink and suppliesink into the pressure chamber. If the ink storing chamber is opened,when the ink cartridge is connected or disconnected or when the inkcartridge is incompletely connected, there is a possibility for ink toleak, whereby stability of the entire printer head is diminished.

Therefore, in order to form the ink storing chamber as a closed space,an auxiliary plate can be used.

It is preferred that the auxiliary plate is made of stainless steel(SUS) or nickel (Ni).

After the auxiliary plate is patterned to a pattern which is suitablefor making the ink storing chamber as a closed space, a photosensitivedry film is bonded onto the auxiliary plate. The bonded photosensitivedry film is exposed to light and patterned to a desired pattern to bebonded to the printer body. At this time, because the photosensitive dryfilm is used as a portion for bonding the auxiliary plate to the printerhead, the photosensitive dry film is patterned such that it is suited toa lower structure of the printer head to which it is bonded.

By bonding the patterned auxiliary plate through the photosensitive dryfilm to a lower part of the substrate, the ink storing chamber isclosed. As a bonding method, a method which is the same as that used forbonding the nozzle plate can be employed.

Also, by simultaneously bonding the nozzle plate and the auxiliaryplate, the number of manufacturing processes can be decreased.

The auxiliary plate which is bonded to the body of the printer head, isformed with an ink inlet port through which ink contained in the inkcartridge is supplied to the ink storing chamber.

By closing the ink storing chamber by using the auxiliary plate asdescribed above, stability of the printer head can be improved.

Next, a printer head using shape memory alloy of the present inventionwill be described.

A printer head using shape memory alloy of the present inventioncomprises a substrate; space parts defined at both sides of thesubstrate; a vibrating plate formed on the substrate such that it coversthe space parts, to be vibrated while being changed in its contourdepending upon temperature variation, the vibrating plate including ashape memory alloy layer and a silicon dioxide layer; an electrodeformed on the vibrating plate to have a desired pattern; an insulatinglayer formed to protect the electrode; an ink storing chamber formedbetween the space parts of the substrate for storing ink; a pressurechamber defined on the vibrating plate for containing ink, the pressurechamber discharging ink by vibration of the vibrating plate; a fluidpassage plate formed at a side of the pressure chamber; a fluid passageformed by the fluid passage plate for allowing the ink stored in the inkstoring chamber to flow into the pressure chamber; a nozzle plateattached onto the fluid passage plate for allowing ink to be fired inthe form of droplets when the vibrating plate is vibrated; and aplurality of nozzles formed in the nozzle plate for firing ink to arecording device. The printer head can further comprise an auxiliaryplate coupled to a lower part of the ink storing chamber to cover theink storing chamber.

An entire structure of the printer head is changed depending upon anetching method used for etching the substrate and whether or not anauxiliary plate is used. Typical examples for several cases areillustrated in FIGS. 44 through 47.

FIG. 44 illustrates a case wherein a substrate is etched by a dryetching technique and an auxiliary plate is used, FIG. 45 illustrates acase wherein a substrate is etched by a wet etching technique and anauxiliary plate is used, FIG. 46 illustrates a case wherein a substrateis etched by a dry etching technique and an auxiliary plate is not used,and FIG. 47 illustrates a case wherein a substrate is etched by a wetetching technique and an auxiliary plate is not used.

All of these four types of printer heads can be manufactured by themethods for manufacturing a printer head using shape memory alloy, ofthe present invention, as aforementioned above.

However, in an etching method, when a substrate is etched by a dryetching technique rather than a wet etching technique, integrationdensity of nozzles can be increased and an entire structure can beminiaturized. Also, when a printer head is manufactured using anauxiliary plate rather than not using an auxiliary plate, stability ofthe printer head can be elevated.

FIG. 48 is a plan view schematically illustrating the printer headaccording to the present invention.

In the printer head of the present invention, in order to improve inkfiring capability, it is preferred that sizes of main components aredetermined as described below.

While the size of the pressure chamber can vary depending upon a size ofthe vibrating plate, it is generally preferred that its width (W1) is35-500 μm, its length (L1) is 35-500 μm and its height is 10-200 μm, andit is specifically preferred that its width (W1) is 35-210 μm, itslength (L1) is 35-210 μm and its height is 10-50 μm.

It is preferred that the area of the pressure chamber is substantiallythe same as that of the vibrating plate to prevent pressure from beingdissipated, and the height of the pressure chamber is lowered to allowshock to be easily transferred to a meniscus. Also, if the size of thepressure chamber is small, because a resonance frequency of the pressurechamber is increased, it is preferred that the size of the pressurechamber is small to increase an operation frequency.

It is preferred that the nozzle greatly influencing the formation ofdroplets has a diameter of 20-50 μm.

If the size of the nozzle is excessively small, firing energy may belost in a direction toward an ink supply port due to a viscosity of inkor a crosstalk may be caused. On the contrary, if the size of the nozzleis excessively large, because pressure is lost and the meniscus deeplyenters toward the pressure chamber after firing, problems are caused inthat an air inflow is generated and a time for replenishing ink islengthened.

While the size of the ink supply port can vary depending upon the sizeof the nozzle, when the nozzle has a diameter of 20-50 μm, it ispreferred that its width (W2) is 20-200 μm, its length (L2) is 10-1,000μm and its height is 10-200 μm, and it is specifically preferred thatits width (W2) is 20-100 μm, its length (L2) is 20-200 μm and its heightis 10-50 μm.

If the size of the ink supply port is excessively large, a pressure lossupon firing is increased to affect velocity and the size of droplets.Also, even after ink is fired, because intensity of inertial flowdischarged from the ink supply port is fairly large, the meniscus isexposed out of a nozzle face, thereby to cause wetting. Further, sincestability of the meniscus is deteriorated, firing stability is alsoreduced. On the contrary, if the size of the ink supply port isexcessively small, ink cannot be properly supplied, decreasing operationfrequency.

It is preferred that the size of the ink storing chamber is determinedsuch that its width (W3) is 100-2,000 μm and its height is 50-700 μm,and it is specifically preferred that its width (W3) is 300-1,000 μm andits height is 100-500 μm.

If the size of the ink storing chamber is excessively small, ink cannotbe properly supplied. Accordingly, an operation frequency is decreased,the size and velocity of droplets have a tendency to vary depending uponthe operation frequency, pressure waves are propagated into otherpressure chambers, and a crosstalk is generated. Therefore, the size ofthe ink storing chamber must not be excessively small but be largeenough to sufficiently supply ink into the pressure chamber.

A distance between the ink storing chamber and the pressure chamber isalso considered as one of important factors.

In other words, if a distance between the ink storing chamber and thepressure chamber is excessively long, incoming air bubbles are notreadily discharged out of the nozzle and have a tendency to remainbehind. This tendency hinders ink in flowing, thereby to affect firing.Further, because a viscosity is increased while the ink reaches thepressure chamber, to hinder ink in flowing, a printer head cannot beoperated at a high frequency.

Consequently, it is preferred that the distance between the ink storingchamber and the pressure chamber is as short as possible. In thisconnection, it is preferred that a distance between the ink storingchamber and the pressure chamber (L3) is 10-1,000 μm, and it isspecifically preferred that the distance (L3) is 20-500 μm.

FIG. 50 is a plan view illustrating an actuator of the printer headaccording to the present invention.

In an actuator of a printer head, if the size of a vibrating plate issmall, since it is possible to heat the vibrating plate with only alittle energy, energy consumption is decreased, heating and coolingrapidly proceed thereby to elevate reactivity, and integration densityof nozzles can be raised thereby enabling an entire structure to beminiaturized.

Since various problems as described above are caused in the actuatorwhen the size of the vibrating plate is large, it is preferred that thesize of the vibrating plate is determined such that its width is 25-500μm, its length is 25-500 μm and its thickness is 0.3-10 μm, and it isspecifically preferred that its width is 25-250 μm, its length is 25-250μm and its thickness is 0.8-7 μm.

If the shape memory alloy is thick and an area thereof is wide, sincevarious problems as described above are caused, it is preferred that theshape memory alloy has a thickness of 0.3-5 μm. Also, it is preferredthat the size of a portion of the shape memory alloy, which is exposed,is determined such that its width is 35-500 μm and its length is 35-500μm, and it is specifically preferred that its width is 35-210 μm and itslength is 35-210 μm.

Moreover, if the silicon dioxide layer serving as the second thin filmis thick, energy consumption is increased when the shape memory alloy isflattened by heating, and if the silicon dioxide layer is thin,restoring force for restoring the shape memory alloy to its flexed stateupon cooling is reduced. Accordingly, it is preferred that the silicondioxide layer has a thickness of 0.3-2.0 μm.

As described above, if the shape memory alloy used as the vibratingplate is thin in its thickness and narrow in its area, since heatingproceeds rapidly, heating time and cooling time are shortened whereby anoperation frequency can be increased. Further, due to the fact that theshape memory alloy is heated with only a little energy, energyconsumption is reduced, and heat loss is lowered whereby energy consumedupon firing ink can be lessened.

In addition, since an interval between two adjoining nozzles can beshortened, integration density of nozzles can be elevated, and sinceresidual vibration due to pressure waves after firing is reduced, stablefiring can be accomplished.

FIG. 50 is a plan view illustrating an actuator of the printer headaccording to the present invention.

In order to shorten a heating time by reducing energy consumption uponheating while securing a volumetric displacement of the pressurechamber, which is sufficient for firing ink, it is preferred that thewidth (d) of the vibrating plate is decreased and the length (l) of thevibrating plate is lengthened.

While it is preferred that a ratio between the width (d) and the length(l) of the vibrating plate is generally 1:1-1:2, the ratio can be varieddepending upon a printer head used.

FIG. 49 is a cross-sectional view schematically illustrating a firingdevice of the printer head according to the present invention. In theprinter head using shape memory alloy of the present invention, inksupplied from the ink cartridge which is connected to the ink storingchamber through the ink storing chamber and the fluid passage to thepressure chamber, is fired onto a recording medium while passing throughpaths described below.

While the shape memory alloy layer 243 of the vibrating plate sectionhas a flattened configuration in its original configuration, it has aresidual compression stress in the course of forming it as a film onto asubstrate by deposition, etc. Accordingly, it is possible to change amagnitude of the residual compression stress which remains in the shapememory alloy, depending upon deposition conditions, a thermal treatingtemperature, a time, etc. when performing deposition on the substrate.

If space parts are formed in lower parts of the substrate by etchingportions of the substrate, the shape memory alloy is flexurally deformeddue to a buckling phenomenon by the compression stress which remains inthe silicon dioxide layer. The shape memory alloy is maintained as it isflexurally deformed.

If electric power is applied to the printer head, electric power issupplied to the electrode 244 and heat is generated in the electrode244. By the heat generated in the electrode 244, the shape memory alloy243 which is in a flexurally deformed state, is heated. When heated, theshape memory alloy 243 is flattened to be returned to its originalconfiguration, and in this manner, volume of the pressure chamber 250 isreduced and ink is fired through the plurality of nozzles.

On the contrary, if the shape memory alloy 243 is cooled, since theflexural deformation is generated by the residual compression stress ofthe silicon dioxide, volume of the pressure chamber 250 is increasedagain, and ink is replenished by an amount of increased volume.

At this time, because the silicon dioxide layers 241 which are formed onthe surfaces of the substrate have elasticity by which they are flexedby themselves, the silicon dioxide layers 241 provide restoring forcefor enabling the shape memory alloy 243 which is flattened by beingheated, to be flexurally deformed while being cooled.

In the printer head using shape memory alloy, these processes arerepeated to continuously fire ink, thereby to perform a printingoperation.

As described above, in the present invention, by using shape memoryalloy of the form of a thin film-shaped configuration manufactured by asemiconductor thin film manufacturing process and by manufacturing theprinter head by forming a lower structure using an etching technique,reliability for the printer head structure and productivity of theprinter head are improved.

Further, the present invention provides an entire structure of a printerhead using shape memory alloy, which is not described in theconventional art. In addition, due to the fact that sizes of thecomponents constituting the printer head using shape memory alloy aredecreased, integration density of nozzles is elevated, thereby improvingprinting resolution.

Reference will now be made in greater detail to a preferred embodimentof the invention, an example of which is illustrated in the accompanyingdrawings. Wherever possible, the same reference numerals will be usedthroughout the drawings and the description to refer to the same or likeparts.

FIGS. 4 through 12 are cross-sectional views for explaining a method formanufacturing a printer head using shape memory alloy, which does notuse an auxiliary plate, in accordance with an embodiment of the presentinvention.

By thermally oxidizing both surfaces of a silicon substrate 40, a pairof silicon dioxide layers 41 and 42 are formed on both surfaces of thesilicon substrate 40, respectively. A shape memory alloy 43 is depositedby sputtering onto the silicon dioxide layer 41 which is formed on thesurface of the substrate 40 by thermal oxidation, and then, is thermallytreated, that is, baked.

The shape memory alloy 43 which is deposited and thermally treated, ispatterned by photolithography, and the silicon dioxide layers 41 and 42which are formed on both surfaces of the substrate 40, respectively, arealso patterned by photolithography.

An electrode 44 is formed such that it covers the patterned shape memoryalloy 43 and the silicon dioxide layer 41 and it does not covervibrating plate sections.

After the electrode 44 is formed, an insulating layer 44 a is depositedonto the electrode 44. After the insulating layer 44 a is deposited, thesubstrate 40 is wholly etched by a wet etching technique to define anink storing chamber 45 and space parts 46 which are arranged below thevibrating plate sections, thereby to complete a body of a printer head.

A nozzle plate 47 in which a plurality of nozzles 49 are defined isseparately formed. A photosensitive dry film is applied onto the nozzleplate 47 which is formed. Thereafter, by patterning the photosensitivedry film using photolithography, a fluid passage plate 48 is prepared.

The nozzle plate 47 and the fluid passage plate 48 are coupled to thebody of the printer head, to complete the printer head.

FIGS. 13 through 22 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy, which doesnot use an auxiliary plate, in accordance with another embodiment of thepresent invention.

By thermally oxidizing both surfaces of a silicon substrate 50, a pairof silicon dioxide layers 51 and 52 are formed on both surfaces of thesilicon substrate 50, respectively. A shape memory alloy 53 is depositedby sputtering onto the silicon dioxide layer 51 which is formed on thesurface of the substrate 50 by thermal oxidation, and then, is thermallytreated, that is, baked.

The shape memory alloy 53 which is deposited and thermally treated, ispatterned by photolithography, and the silicon dioxide layers 51 and 52which are formed on both surfaces of the substrate 50, respectively, arealso patterned by photolithography.

An electrode 54 is formed such that it covers the patterned shape memoryalloy 53 and the silicon dioxide layer 51 and it does not covervibrating plate sections.

After the electrode 54 is formed, an insulating layer 54 a is depositedonto the electrode 54. After the insulating layer 54 a is deposited, thesubstrate 50 is wholly etched by a dry etching technique to define anink storing chamber 55 and space parts 56 which are arranged below thevibrating plate sections.

A photosensitive dry film is applied onto the electrode 54. Then, thephotosensitive dry film is patterned by photolithography to prepare afluid passage plate 58, thereby to complete a body of a printer head.

A nozzle plate 57 in which a plurality of nozzles 59 are defined, isseparately formed. The nozzle plate 57 is coupled onto the fluid passageplate 58 to complete the printer head.

FIGS. 23 through 32 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy, which doesnot use an auxiliary plate, in accordance with another embodiment of thepresent invention.

By thermally oxidizing both surfaces of a silicon substrate 60, a pairof silicon dioxide layers 61 and 62 are formed on both surfaces of thesilicon substrate 60, respectively. A shape memory alloy 63 is depositedby sputtering onto the silicon dioxide layer 61 which is formed on thesurface of the substrate 60 by thermal oxidation, and then, is thermallytreated, that is, baked.

The shape memory alloy 63 which is deposited and thermally treated, ispatterned by photolithography, and the silicon dioxide layers 61 and 62which are formed on both surfaces of the substrate 60, respectively, arealso patterned by photolithography.

An electrode 64 is formed such that it covers the patterned shape memoryalloy 63 and the silicon dioxide layer 61 and it does not cover avibrating plate sections.

After the electrode 64 is formed, an insulating layer 64 a is depositedonto the electrode 64. A photosensitive dry film is applied onto theinsulating layer 64 a which is formed. Then, the photosensitive dry filmis patterned by photolithography to prepare a fluid passage plate 68.

A nozzle plate 67 in which a plurality of nozzles 69 are defined, isseparately formed. The nozzle plate 67 is coupled onto the fluid passageplate 68.

After the nozzle plate 67 is coupled onto the fluid passage plate 68,the substrate 60 is wholly etched by a dry etching technique to definean ink storing chamber 65 and space parts 66 which are arranged belowthe vibrating plate sections, thereby to complete a printer head.

FIGS. 33 through 43 are cross-sectional views for explaining a methodfor manufacturing a printer head using shape memory alloy, which uses anauxiliary plate, in accordance with another embodiment of the presentinvention.

In the present embodiment, processes for manufacturing a printer head(see FIGS. 33 through 40) are the same as those employed in theembodiment shown in FIGS. 4 through 12, and steps for manufacturing andattaching a separate auxiliary plate are added.

An auxiliary plate 82 is patterned to a pattern which is suitable forbeing adapted to a printer head manufactured by the above embodiments. Aphotosensitive dry film 84 is applied onto the auxiliary plate 82 whichis patterned. The photosensitive dry film 84 is patterned depending upona lower structure of a printer head to be bonded.

The patterned auxiliary plate 82 and the nozzle plate 77 aresimultaneously attached to a body of a printer head.

FIG. 44 is a cross-sectional view illustrating a printer head usingshape memory alloy, manufactured according to the present invention,wherein a substrate is etched by a dry etching technique and anauxiliary plate is used.

A printer head of this embodiment has an ink storing chamber 95 which isformed in a center portion of a substrate 90 by a dry etching technique,and space parts 96 which are formed on the left and right of thesubstrate 90, respectively. A vibrating plate which comprises a silicondioxide layer 91 and a shape memory alloy layer 93 is disposed above thespace parts 96, and an electrode 94 is formed on the vibrating plate.

An insulating layer 94 a is formed on the electrode 94, and a fluidpassage plate 98 is formed on a side of the insulating layer 94 a. Anozzle plate 97 in which a plurality of nozzles 99 are formed, is formedon the fluid passage plate 98. A fluid passage 101 is defined by thefluid passage plate 98, and a pressure chamber 100 is defined betweenthe fluid passage 101 and the fluid passage plate 98.

An auxiliary plate 102 which is formed with a photosensitive dry film104, is coupled to a lower part of the substrate 90 to close the inkstoring chamber 95.

FIG. 45 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention, wherein a substrate is etched by a wet etching technique andan auxiliary plate is used.

A printer head of this embodiment has an ink storing chamber 115 whichis formed in a center portion of a substrate 110 by a wet etchingtechnique, and space parts 116 which are formed on the left and right ofthe substrate 110, respectively. A vibrating plate which comprises asilicon dioxide layer 111 and a shape memory alloy layer 113 is disposedabove the space parts 116, and an electrode 114 is formed on thevibrating plate.

An insulating layer 114 a is formed on the electrode 114, and a fluidpassage plate 118 is formed on a side of the insulating layer 114 a. Anozzle plate 117 in which a plurality of nozzles 119 are formed, isformed on the fluid passage plate 118. A fluid passage 121 is defined bythe fluid passage plate 118, and a pressure chamber 120 is definedbetween the fluid passage 121 and the fluid passage plate 118.

An auxiliary plate 122 which is formed with a photosensitive dry film124, is coupled to a lower part of the substrate 110 to close the inkstoring chamber 115.

FIG. 46 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention, wherein a substrate is etched by a dry etching technique andan auxiliary plate is not used.

A printer head of this embodiment has an ink storing chamber 135 whichis formed in a center portion of a substrate 130 by a dry etchingtechnique, and space parts 136 which are formed on the left and right ofthe substrate 130, respectively. A vibrating plate which comprises asilicon dioxide layer 131 and a shape memory alloy layer 133 is disposedabove the space parts 136, and an electrode 134 is formed on thevibrating plate.

An insulating layer 134 a is formed on the electrode 134, and a fluidpassage plate 138 is formed on a side of the insulating layer 134 a. Anozzle plate 137 in which a plurality of nozzles 139 are formed, isformed on the fluid passage plate 138. A fluid passage 141 is defined bythe fluid passage plate 138, and a pressure chamber 140 is definedbetween the fluid passage 141 and the fluid passage plate 138.

FIG. 47 is a cross-sectional view illustrating another printer headusing shape memory alloy, manufactured according to the presentinvention, wherein a substrate is etched by a wet etching technique andan auxiliary plate is not used.

A printer head of this embodiment has an ink storing chamber 155 whichis formed in a center portion of a substrate 150 by a wet etchingtechnique, and space parts 156 which are formed on the left and right ofthe substrate 150, respectively. A vibrating plate which comprises asilicon dioxide layer 151 and a shape memory alloy layer 153 is disposedabove the space parts 156, and an electrode 154 is formed on thevibrating plate.

An insulating layer 154 a is formed on the electrode 154, and a fluidpassage plate 158 is formed on a side of the insulating layer 154 a. Anozzle plate 157 in which a plurality of nozzles 159 are formed, isformed on the fluid passage plate 158. A fluid passage 161 is defined bythe fluid passage plate 158, and a pressure chamber 160 is definedbetween the fluid passage 161 and the fluid passage plate 158.

In the drawings and specification, there have been disclosed typicalpreferred embodiments of the invention and, although specific terms areemployed, they are used in a generic and descriptive sense only and notfor purposes of limitation, the scope of the invention being set forthin the following claims.

What is claimed is:
 1. A method for manufacturing a printer head usingshape memory alloy, comprising the steps of: preparing a siliconsubstrate having a flat configuration; thermally oxidizing the siliconsubstrate to form a pair of silicon dioxide layers on both surfaces ofthe silicon substrate, respectively; forming a shape memory alloy layeron one of the pair of silicon dioxide layers by a semiconductor thinfilm forming process; thermally treating the formed shape memory alloylayer; patterning the shape memory alloy layer; patterning the silicondioxide layers formed on both surfaces of the silicon substrate,respectively; forming an electrode on the shape memory alloy layer tohave a desired pattern; forming an insulating layer for protecting theelectrode; forming a body of the printer head by etching the siliconsubstrate on which the electrode and insulating layer are formed;separately forming a nozzle plate into which a plurality of nozzles areformed; forming a fluid passage plate by bonding a photosensitive dryfilm onto the nozzle plate and patterning the photosensitive dry film;and bonding the nozzle plate and the fluid passage plate onto the bodyof the printer head.
 2. A method as claimed in claim 1, wherein theelectrode is made of material selected from a group consisting ofaluminum (Al), gold (Au), platinum (Pt) and silver (Ag).
 3. A method asclaimed in claim 1, further comprising the steps of: forming anauxiliary plate; applying a photosensitive dry film on the auxiliaryplate and patterning the photosensitive dry film; and bonding theauxiliary plate on which the photosensitive dry film is patterned, ontothe other of the pair of silicon dioxide layers.
 4. A method as claimedin claim 3, wherein the auxiliary plate is made of stainless steel (SUS)or nickel (Ni).
 5. A method as claimed in claim 3, wherein the auxiliaryplate is bonded onto the other of the pair of silicon dioxide layers atthe same time when the nozzle plate and the fluid passage plate arebonded onto the body of the printer head.
 6. A method as claimed inclaim 1, wherein the silicon dioxide layer has a thickness of 0.3-2 μm.7. A method as claimed in claim 1, wherein the shape memory alloy has athickness of 0.3-5 μm.
 8. A method as claimed in claim 1, wherein thesilicon substrate is etched by a dry etching technique.
 9. A method formanufacturing a printer head using shape memory alloy, comprising thesteps of: preparing a silicon substrate having a flat configuration;thermally oxidizing the silicon substrate to form a pair of silicondioxide layers on both surfaces of the silicon substrate, respectively;forming a shape memory alloy layer on one of the pair of silicon dioxidelayers by a semiconductor thin film forming process; thermally treatingthe formed shape memory alloy layer; patterning the shape memory alloylayer; patterning the silicon dioxide layers formed on both surfaces ofthe silicon substrate, respectively; forming an electrode on the shapememory alloy layer to have a desired pattern; forming an insulatinglayer for protecting the electrode; applying a photosensitive dry filmonto the insulating layer and patterning the photosensitive film;forming a body of the printer head by dry etching the formed siliconsubstrate; separately forming a nozzle plate into which a plurality ofnozzles are formed; and bonding the nozzle plate onto the body of theprinter head.
 10. A method as claimed in claim 9, wherein the electrodeis made of material selected from a group consisting of aluminum (Al),gold (Au), platinum (Pt) and silver (Ag).
 11. A method as claimed inclaim 9, further comprising the steps of: forming an auxiliary plate;applying a photosensitive dry film on the auxiliary plate and patterningthe photosensitive dry film; and bonding the auxiliary plate on whichthe photosensitive dry film is patterned, onto the other of the pair ofsilicon dioxide layers.
 12. A method as claimed in claim 11, wherein theauxiliary plate is made of stainless steel (SUS) or nickel (Ni).
 13. Amethod as claimed in claim 11, wherein the auxiliary plate is bondedonto the other of the pair of silicon dioxide layers at the same timewhen the nozzle plate and the fluid passage plate are bonded onto thebody of the printer head.
 14. A method as claimed in claim 9, whereinthe silicon dioxide layer has a thickness of 0.3-2 μm.
 15. A method asclaimed in claim 9, wherein the shape memory alloy has a thickness of0.3-5 μm.
 16. A method for manufacturing a printer head using shapememory alloy, comprising the steps of: preparing a silicon substratehaving a flat configuration; thermally oxidizing the silicon substrateto form a pair of silicon dioxide layers on both surfaces of the siliconsubstrate, respectively; forming a shape memory alloy layer on one ofthe pair of silicon dioxide layers by a semiconductor thin film formingprocess; thermally treating the formed shape memory alloy layer;patterning the shape memory alloy layer; patterning the silicon dioxidelayers formed on both surfaces of the silicon substrate, respectively;forming an electrode on the shape memory alloy layer to have a desiredpattern; forming an insulating layer for protecting the electrode;applying a photosensitive dry film onto the insulating layer andpatterning the photosensitive film to define a body of the printer head;separately forming a nozzle plate into which a plurality of nozzles areformed; bonding the nozzle plate onto the body of the printer head; anddry etching the silicon substrate.
 17. A method as claimed in claim 16,wherein the electrode is made of material selected from a groupconsisting of aluminum (Al), gold (Au), platinum (Pt) and silver (Ag).18. A method as claimed in claim 16, further comprising the steps of:forming an auxiliary plate; applying a photosensitive dry film on theauxiliary plate and patterning the photosensitive dry film; and bondingthe auxiliary plate on which the photosensitive dry film is patterned,onto the other of the pair of silicon dioxide layers.
 19. A method asclaimed in claim 18, wherein the auxiliary plate is made of stainlesssteel (SUS) or nickel (Ni).
 20. A method as claimed in claim 18, whereinthe auxiliary plate is bonded onto the other of the pair of silicondioxide layers at the same time when the nozzle plate and the fluidpassage plate are bonded onto the body of the printer head.
 21. A methodas claimed in claim 16, wherein the silicon dioxide layer has athickness of 0.3-2 μm.
 22. A method as claimed in claim 16, wherein theshape memory alloy has a thickness of 0.3-5 μm.
 23. A printer head usingshape memory alloy comprising: a substrate; space parts defined at bothsides of the substrate; a vibrating plate formed on the substrate suchthat it covers the space parts, to be vibrated while being changed inits contour depending upon temperature variation, the vibrating plateincluding a shape memory alloy layer and a silicon dioxide layer; anelectrode formed on the vibrating plate to have a desired pattern; aninsulating layer formed to protect the electrode; an ink storing chamberformed between the space parts of the substrate for storing ink; apressure chamber defined on the vibrating plate for containing ink, thepressure chamber discharging ink by vibration of the vibrating plate; afluid passage plate formed at a side of the pressure chamber; a fluidpassage formed by the fluid passage plate for allowing the ink stored inthe ink storing chamber to flow into the pressure chamber; a nozzleplate attached onto the fluid passage plate for allowing ink to be firedin the form of droplets when the vibrating plate is vibrated; and aplurality of nozzles formed in the nozzle plate for firing ink to arecording device.
 24. A printer head using shape memory alloy as claimedin claim 23, further comprising: an auxiliary plate coupled to a lowerpart of the ink storing chamber to cover the ink storing chamber.
 25. Aprinter head using shape memory alloy as claimed in claim 24, whereinthe auxiliary plate is made of stainless steel (SUS) or nickel (Ni). 26.A printer head using shape memory alloy as claimed in claim 23, whereinthe pressure chamber has a width of 35-500 μm, a length of 35-500 μm anda height of 10-200 μm.
 27. A printer head using shape memory alloy asclaimed in claim 23, wherein the nozzle has a diameter of 20-50 μm. 28.A printer head using shape memory alloy as claimed in claim 23, whereinthe fluid passage has a width of 20-200 μm, a length of 10-1,000 μm anda height of 10-200 μm.
 29. A printer head using shape memory alloy asclaimed in claim 23, wherein the ink storing chamber has a width of100-2,000 μm and a height of 50-700 μm.
 30. A printer head using shapememory alloy as claimed in claim 23, wherein a distance between the inkstoring chamber and the pressure chamber is 10-1,000 μm.
 31. A printerhead using shape memory alloy as claimed in claim 23, wherein an exposedportion of the shape memory alloy layer has a transverse of 35-500 μmand a longitude of 35-500 μm.
 32. A printer head using shape memoryalloy as claimed in claim 23, wherein the vibrating plate has atransverse of 25-500 μm, a longitude of 25-500 μm and a thickness of0.3-10 μm.
 33. A printer head using shape memory alloy as claimed inclaim 32, wherein a thickness of the shape memory alloy layer is 0.3-5μm.
 34. A printer head using shape memory alloy as claimed in claim 32,wherein a thickness of the silicon dioxide layer as being a second thinfilm is 0.3-2.0 μm.
 35. A printer head using shape memory alloy asclaimed in claim 23, wherein a thickness of the shape memory alloy layeris 0.3-5 μm.
 36. A printer head using shape memory alloy as claimed inclaim 23, wherein a thickness of the silicon dioxide layer as being asecond thin film is 0.3-2.0 μm.
 37. A printer head using shape memoryalloy as claimed in claim 23, wherein the electrode is made of materialselected from a group consisting of aluminum (Al), gold (Au), platinum(Pt) and silver (Ag).